Body motion and position sensing, recognition and analytics from an array of wearable pressure sensors

ABSTRACT

Pressure-sensor based arrays are integrated into a control device that detects the position, motion, or movement of a one or more body parts of a user to recognize and translate the motion into a unique user-motion profile. The user motion profile may be independently analyzed or recognized as a discrete motion or gesture and used as input or commands for the control device itself or as a signal or set of signals that yields an output signal to a companion device. The pressure sensors can be attached to any body part of a user, such as the user&#39;s wrist or ankle. Motion or position, or changes therein, of the user generates an output signal that may be used to control a companion device. The source of the detectable signal is the pressure-based sensor array that yields a pressure data profile that is translated into an output signal to control the companion device.

All references cited herein, including but not limited to patents andpatent applications, are incorporated by reference in their entirety.This application is a continuation of U.S. patent application Ser. No.16/155,839, filed Oct. 9, 2018, which claims priority to U.S.Provisional 62/570,058, filed Oct. 9, 2017.

BACKGROUND OF THE INVENTION

A wide variety of electrical and mechanical devices can be coupled witha separate control device that takes input from a user that is sensed,recognized, and analyzed to interpret the input from the user andconvert that input into output that can be used for a variety ofpurposes. Input from the body of a user that is sensed and recognized bya control device can be communicated with a companion device and thisprocess of sensing, recognition, and analysis enables the user tomanually manipulate the control device to create data output. This dataoutput can be used for independent analysis of the motion of the user,or translated into command or control instructions to the companiondevice. Examples include keyboards, touchpads, computer mice,microphones, numeric keypads, pedals and a variety of other inputdevices that are in common use and that are typically operated by handor by foot. In these examples, motion imparted by the user to thedevice, such as by striking individual keys of the keyboard, moving acomputer mouse, entering sound into a microphone, or actuating a pedal,results in an output that instructs the companion device, such as acomputer to implement certain steps. As will be apparent from theseexamples, coupling the specific input from the user to the desiredoutput to the companion device is an integrated process that is designedso that the most convenient way for the user to provide the input istranslated into the data output that is necessary for the companiondevice to function.

The wide variety of input devices reflects the wide range of companiondevices that can be controlled by manual input from a user, andincludes, but is not limited to, computers, telephones, video displays,control and security systems, and virtually any device or system havinga controlling mechanism or an interface wherein the user directs controlof the device through an input or interface.

Most users are familiar with input devices such as keyboards and numerickeypads where manual contact with a mechanical key or button or touchinga space in a screen or visual field translates into a single letter,number, or other instruction such as turning a device or or off orcausing the companion device to execute some predetermined function. Inorder to make these input devices faster, more efficient, and generallymore convenient, several motion or movement detector apparatus have beendeveloped that can be physically attached to a body appendage, such as ahand, wrist, or foot of a user and can translate motion or gestures bythe user into data input or instructions, even if performed completelyin “space,” i.e. where the user makes no direct contact with any inputdevice.

U.S. Patent Publications 2016/0091980 (Apple Inc.) and 2017/0031453(Philips N. V.), specifically incorporated herein by reference, eachdescribe apparatus that detect hand movements using optical sensors thatrely on a paired optical emitter and a series of optical detectors todiscern hand motions based on differences in the light passed throughthe anatomical structures of the wrist as the hand makes certaingestures. These devices are designed to detect gestures based on thedetection of light and then to translate the light signals into datainput. For example, by arranging light emitting devices and lightdetecting sensing devices around the wrist, these devices sensedifference in light transmitted through bones, muscles and tendons andthe user moves their hand and, based on the motion of the user's handand wrist, the devices translate the difference in transmitted lightinto instructions that can control a watch, a computer, or anotherdevice. For example, the system may detect a hand waving motion of auser to signify some action, such as turning a computer on or off, andcan detect the differences in the light transmitted through tissueduring the movement of a user's individual fingers to translatedifferent finger motion into discrete signals to control a companiondevice.

These existing devices are typically coupled to a data processing unitthat translates the sensed light signals from the user's motions orgestures into a particular output signal. For example, the combinationof the sensor and the data processing unit might detect the differencein the optical characteristics of a user's bones, muscles, and tendonsas a user extends one finger as opposed to two fingers, recognize theseas different signals, and then instruct a companion device to performdifferent functions. Accordingly, a change in hand and finger motionbetween extending one finger versus exending two fingers could be thedifference, for example, between turning a computer or cell phone “on”or off.” These devices can also be combined with motion and electricalsensors to generate a mixture of signal inputs or a multiplex thatcombine with optical emmitters and sensors to reflect the motion,movement, or gesture of a user.

While devices that are primarily based on optical sensing arrays candistinguish a number of individual movements of a user, these deviceshave certain drawbacks inherent in the use of light or electricalsignals to detect motion, including the inherent potential forbackground noise in the form of extraneous light or electrical signalsto compromise the accuracy of the detected signal. Furthermore, lightemitting devices tend to require significant power to operate and thepower requirements can result in the requirement for associated largeand bulky power storage devices or result in limited operational lifefor any device based on light or electrical sensors.

SUMMARY OF THE INVENTION

The present invention is a pressure-sensor based array integrated into acontrol device that detects the position, motion, or movement of a oneor more body parts of a user to recognize and translate the motion intoa unique user-motion profile. The user motion profile may beindependently analyzed or recognized as a discrete motion or gesture andused as input or commands for the control device itself or as a signalor set of signals that yields an output signal to a companion device.The pressure sensors can be attached to any body part of a user, but arepreferentially attached to a user's wrist or ankle or other body partthat can be surrounded by a plurality of sensors forming an array andthat is commonly used to provide input to a companion device. Forexample, a pressure-sensor-based device attached to the wrist detectsmultiple individual components based on underlying physiologicalstructures comprising movements of the muscles, tendons, and bones inthe user's wrist, hand, arm, and fingers to translate the position,motion, or movement into a detectable signal that can be used togenerate an output signal that is decoded to control the companiondevice. The source of the detectable signal is the pressure-based sensorarray attached to the appendage of the user, for example, an arrayattached to the wrist detects individual motion of the muscles, tendons,and bones in the same fashion that an array attached to the anklesimilarly detects motion of the muscles, tendons, and bones of the footor toes to generate a signal that yields an output signal that controlsa companion device.

For ease of reference, the term “motion” is used hereafter to describeeach of sensing an initial, resting, or baseline position of a portionof the user's body as a first position, sensing a transitional motionaway from the first position, such as a distinct movement or gesturerepresenting a command, and sensing a final or second position, distinctfrom the first position where the difference between the first andsecond position and/or the translational motion is interpreted as asignal or input, preferably to control a companion device. Accordingly,the device of the present invention can sense motion as an activeprocess as the user moves or can detect the difference between theposition of the body at an initial verses and a final position orcombinations of each, recognize these motions or change in positions,and generate a specific motion profile for analysis, includingtranslation into a profile for analysis upon repetition of forinterpretation as a control for a companion device.

Functionally, the device of the invention detects pressure at aplurality of points along and/or around the body part of the user andtakes unique pressure measurements generated by motion to translate thepressure reading values into a unique quantitative pressure profile thatis analyzed and translated into any one or several discrete dataprofiles including, but not limited to motion profiles, discretegestures, and instructions to a companion device. For example, pressuresensors circumferentially located around and that specifically selectedpoints along the interior surface of a band attached to the wristdetects pressure values that are characteristic of the movement of theforearm, the hand, the wrist, the fingers, or any individual unit orcombination thereof, including movement of the individual fingers, bothindividually and collectively two specified numbers or letters of thealphanumeric alphabet. The distinct movements of the body generatedifferent and characteristic pressure values and assembled profiles and,by using a number of pressure measurements both individually andcollectively, these body movements can be recognized and correlated withgestures that are translated into output, such as the commands used tocontrol a computer. Because of the sensitivity and selectivity of thespecific pressure sensors used in the present invention, characteristicmovements of the body part(s) can be used to discriminate between subtlemotions performed by the user, recognized, output as unique quantitatedata profiles, and analyzed as specific motions or ranges of motions,and optionally assigned to specific command and control functions for acompanion device.

To maximize the information obtained from the motion of a user, aplurality of individual pressure sensors are combined to establish apressure sensor array may be combined with different types of sensorsthat are designed to detect other parameters at the same or differentregions of body tissue, including selected portions of tendon,ligaments, muscle, bone, interstitial tissue, veins, arteries, and anybody part that causes static or differential measurements in addition topressure readings at the surface of the skin at a point engaged by anindividual pressure sensor. The combination of the sensor array and theadditional sensor may also include detectors for pulse blood flow orother physiologic parameters as well as sensors for acccelaration,rotation, or changes in an electric or magnetic field. Collectively, thesignals from the all of the sensors create a data output and a sensorprofile wherein each movement of the user's appendage generates specificand quantitative pressure profiles that are unique to the individualmotion and optionally to the individual. Accordingly, the motion of auser holding out a single index finger it is readily distinguished fromthe motion of a user holding out the index and middle finger and theunique and specific pressure sensor profile of each motion or gestureyields a discrete command or data output that is preferably processedinto a pressure-based data profile that is analyzed and may be transltedinto input or command and control instructions for a companion device.

When such an array of sensors comprising the pressure sensor array isdeployed as described herein, a localized, optionally circumferentiallyoriented, pressure data “map” can be constructed for any motion of anyappendage or body part. As the number and density of pressure sensorsincreases, and the individual pressure data values are assembled ingreater numbers, more information regarding the position or motion ofthe underlying body structures is gathered for subsequent analysis andgeneration of an output instruction to a companion device. In the caseof a single sensor spanning the circumference of the wrist, the tension(related to wrist expansion/contraction, as is the case in flexion &extension of the hand) can be determined based on individual andcollective motion of the underlying physiological structures.

When the number of sensors increases and the size of the individualsensors decreases, the sensor size may approach the average tendon size(roughly 4 mm). Accordingly, as the number of sensors increases (forexample an array of more than 6, 8, 10, 12. 14 16, 18, 20, 22, 24, 32 or64 individual sensors), the number of sensors exceeds the number ofunderlying physiological structures whose pressure is being detected andthe sensor data assembled is comprised of a discrete measures of aplurality of individual anatomical structures.

Accordingly, two adjacent sensors may each be detecting a pressurecontribution from any one or more underlying anatomical structures,including but not limited to, one or more tendons, one or more muscles,one or more ligaments, and/or one or more bones. When the number ofsensors approaches double the number of measured body features (such asa combination of tendon, muscle, bone, etc; totaling approximately 18features), then the individual sensors more directly measure individualphysiological structures and particular motions of the appendage can betracked even more precisely using each individual physiologicalstructure, or a combination of one individual physiological structurecombined with a multiplex of sensor data from an additional individualor plurality of individual physiological structures. A signal processingtechnique called de-aliasing allows for separation/targeting of thechanges that affect multiple sensors. A similar technique can allow foradaptation for variation in sensor rotation about the wrist. In cases ofan array comprising fewer sensors then the total number of sensedphysiological structures, (for example 8 sensors in the array disposedaround more than 8 tendons), tendon groups can be tracked and mostnatural hand positions can be determined (including but not limited tohand flexion/extension, adduction/abduction, and various fingerflexion/extension Se Figures ______-______).

The control device may have a dedicated power supply and circuitry toconnect the individual pressure sensors to at least a data storagemedium and optionally logic circuitry for recognizing specific pressureprofiles and analysing same, the signal processing for the quantitativeand unique pressure profiles may be housed either in the control deviceor in a companion device. Accordingly a control device attached to thewrist may process command and control functions generated by thepressure profile or the pressure profile may be communicated to acompanion device such as a computer, phone, game controller, or otherapparatus containing logic circuitry to translate the motion intocommand-and-control functions. Preferably, the data is collected in atleast three, but preferably five or more threshold pressure values. Forexample a particular sensor might detect zero change in orientation ormotion, a small positive change in pressure resulting from motion, alarge positive change in pressure resulting from motion, a smallnegative change in pressure or a large negative change in pressure.Individual threshold values can be preset in addition to discretequantitative values to assemble the unique and quantitative pressureprofile as described herein.

By combining the data from a plurality of individual sensors deployed inthe array, individual pressure profiles corresponding to specificindividual or discrete motions, range of motions, or assembled sets orsubsets of motions can be recognized to establish a motion pattern ordeviation from a pre-existing pattern. Any absolute or relativemeasurement of the motions, ranges, or patterns of motions, can beanalyzed and used to generate a quantitative score that reflects theindividual or combined/multiplex pressure measurements both individuallyor collectively and in comparison to a prior individual motion orassembled set of motions. Individual or collective motion scores can becorrelated with types of user-performed motions that are characteristicof a function intended to be performed by the user or a control orcommand intended by the user to control a companion device.

If the pressure profile is correlated with a particular gesture by theuser, the gesture can each be assigned a command or control function forthe control device or for a companion device. For example, a set ofpressure changes detected across at least six tendons might indicate aspecific hand gesture that corresponds to one particular command output.Similarly small changes in four or more tendons combined with no changesin two tendons might indicate a different specific hand gesture and adifferent particular command output. In practical use, the set ofmuscle, tendon, ligament, and bone orientations and motions created whena user creates a closed first might instruct a companion device to“power on”, while the unique set of muscle, ligament, tendon and bonemotions when a user points an index finger might direct a companiondevice to open a particular program or to “power off”. As described indetail below, a large number of motions and gestures can be measured andassigned different command and control instructions either bypre-programming or in a learning mode at the direction of the user. Allof these functions and many more will be appreciated by one of ordinaryskill in the art from the following description and figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a graphic of six individual metrics (G0-G5) representatingindividual elements of a quantitative gesture detection data profiles ofthe control device of the invention. The combination of metrics, basedon the individual amplitudes of the individual metrics yields a uniqueand quantitative gesture detection score based on the specific,individual pressure values input from the sensor array and reflected inthe metrics G0-G5.

FIG. 2 is a cross-section of a human wrist showing the orientation ofindividual physiological structures including fourteen tendons, theradius and ulna bones, and other internal anatomic structures such thatthe placement of a plurality of individual pressure sensors in closeconforming engagement with the outer dermal layers of the wristgenerates unique and quantitative pressure profiles based on differentconfigurations and motions of the forearm, wrist, hand, and fingers.

FIG. 3A and 3B are the control device of the invention in conformingengagement with an appendage of a user showing the orientation of thetendons in physiological structures of the human wrist with sensorsplaced in close proximity thereto.

FIG. 4 is an assembly abnormal human hand gestures made up of armmovements, finger movements, and palm movements.

FIG. 5 is an assembly of gestures and commands that might be correlatedto pressure sensor data and showing how certain gestures would betranslated into commands for three different controller examples.

FIG. 6 is a chart showing representative change in physiologicalinterfacial pressure across fourteen individual tendons located in theright hand wrist. Blank fields indicate no change in pressure, singledownward arrows indicate a small reduction in pressure values, dualdownward arrows indicate a larger reduction in pressure values, singleupward arrows indicate a small increase in pressure values, and dualupward arrows indicate a larger increase in pressure values. The leftaxis contains the at least 11 individual orientations orcommand-and-control functions that can be assigned to the specificcombination of pressure changes across the tendons as measured.

DETAILED DESCRIPTION OF THE INVENTION

The invention is each of a pressure-sensor-based control devicecomprised of individual pressure sensors forming an array, the controldevice combined with a companion device, and methods for their use thatemploy a plurality of pressure sensors to detect a user's motion togenerate data, data profiles, quantitative pressure signatures, definedgestures, control instructions, commands or other input that aredirected to the control device or to the companion device(s) based onsensor input from a plurality of sensors that form an array. The controldevice is physically attached to an appendage of the user by anystructural or mechanical expedient that causes the array to be securelypositioned to the appendage such that the pressure-based sensors arecapable of detecting pressure generated by sub-dermal anatomicstructures positioned in any of a first configuration or initial restingstate, a series of movements comprising a transitional movement state orrange of states, and a resulting second state that follows thetransitional movement, is different than the first configuration and maybe followed by any number of distinct following configurations.

Although the sensor input relies on the plurality of pressure sensors,additional optical sensors, acceleration or inertial sensors, gyroscopesor other rotational sensors, and magnetic sensors, can independentlyprovide input relating to the motion of the user and can be combinedwith the pressure sensor data as described herein. In some embodimentsdata from the pressure sensor array is integrated with data from atleast 3 of each of accelerometers, gyroscopes, and magnetometers.

Based on the detected motion, the control device generates input to thecontrol device itself or to the companion device, and the device and/orthe companion device performs an operation based on the input. The inputfrom the control device can be combined with other conventional userinterface mechanism such as keyboards, keypads, touchscreens and thelike such that the control device of the present invention operates inconcert with an existing input device. Examples of the companion devicesinclude but are not limited to computers, cellular phones, video displayapparatus, gaming, sports or other interactive consoles, robotic motionand other remote manipulation systems, musical instruments, medicalequipment, automobiles, appliances and virtually any electronic ormechanical device capable of accepting an input to control the status oroperation of the companion device.

In some examples, the plurality of pressure sensors forming the pressuresensing array are located on the control device itself or located on anattachment to the companion device containing the sensor array. Forexample, the sensor array can be located in an integrated assembly ofthe control device and a wristwatch as the companion device or can be adiscrete advice that is separate from a wristwatch but is operablyconnected by any conventional communication mechanism such as Bluetooth,a wired connection, optical or wireless transmissions or any othercommonly available data transmission mechanism or method.

The pressure sensor arrays generate a unique and specific pressureprofile based on sub-dermal pressures exerted by the user's tendons,ligaments, skin, muscles, and bones. In some embodiments, the controldevice is comprised of functional sensing materials that areconventionally used in clothing or other worn items attached to the usersuch as watches, hats, jewelry, bandages or other constructs that causethe pressure sensor array to be held in close conforming engagement withthe surface of the skin and to maintain a substantially consistentorientation at the surface of the user's body such that absolute orrelative motion by the user causes change in the specific pressureprofile sensed by the control device.

EXAMPLE 1 Pressure Sensor-Based Control Device Integrated IntoConventional Band Materials (Fabric, Leather, Silicone, Polymer, Metal,or Combination)

In this example, the pressure sensor array is embedded into a watch bandand the band functions as a control device. The sensors surround thewrist circumferentially, and due to the absence of rigid sensorcomponents, are held in conforming engagement with the surface of theskin of the user as with a typical watch band. Flexible individualpressure sensors form an array and are integrated or embedded as part ofthe band materials such that the band area comprises a sensor array thatcovers the substantial circumference of the wrist, or that substantialcircumference not otherwise occupied by a control device or a companiondevice. Accordingly, where the sensing array covers the entirety of theband, the array spans the entire wrist such that the sensors arepositioned about the entire circumference of the appendage and thisconfiguration maximizes the sensing inputs from the individual pressuresexerted at the skin surface and maximizes the data as the number ofsensors increases. As will readily be appreciated, a greater number ofsensors may be disposed around a smaller arc surrounding an appendageand, depending on the underlying physiology, the resulting data profilewill be dependent on both the area covered by the sensors as well as thenumber of sensors disposed in the array. Preferred embodiments for boththe number of sensors and the extent of coverage around the bodyappendage are described below and in the accompanying Figures.

Viewing the band along an axis traversing the center of the wrist, theangle delta (δ) defines the discrete portion(s) of the circumference inwhich the individual sensors are deployed. For example, if the sensorsare deployed about the entire circumference of the band, the angle δwould be 360°. Similarly, if a portion of the band is occupied by ahousing of a control device or companion device, such that theindividual sensors are disposed about three quarters of thecircumference of the band the angle δ would be 270°. The specific anglescontemplated by the pressure sensor array of the invention includeangles δ greater than 90°, greater than 120°, greater than 150°, greaterthan 180°, greater than 210°, greater than 240°, greater than 270°, andgreater than 330°, and integral values therein.

EXAMPLE 2 Sensor Specifications

The individual sensor is preferably comprised of an ionic sensor asdescribed in U.S. Pat. Nos. 9,170,166; 9,459,171; 9,739,679 (and pendingapplications US 2017/0059434 A1 & application on Fabric sensor filed May25th). The sensor is preferably fabric-based, thin (500 μm or typically1.5 mm), and conforms to the external surface of curved surfaces of thebody such as the wrist, forearm, ankle, cranium, neck, chest, orabdomen. The sensors can also be integrated into clothing and customizedin size, material, and sensitivity depending on the application.

The individual sensors must have an operational pressure range to detectthe largest pressure changes from gestures and account for the baselinepressure from the tension of the band (ranging from 0-100 mmHg). Biasingstructures can change the minimum operational pressure away from 0 andmaintain the size of the range of maximum sensitivity (for example 40-70mmHg for a region of high baseline pressure). An operation range of 0-30mmHg (with biasing structures) is ideal but can go as low as 0-10 mmHgor as high as 0-120 mmHg. For basic gesture detection , changes inpressure as low as 4 mmHg must be detectable and distinct from noisethus a sensitivity (pressure resolution) and noise level no greater than1 mmHg and a repeatability error no greater than 50%. For advancegesture detection changes in pressure as low as 0.5-1 mmHg must bedetectable. Thus sensitivity and noise level are no greater than 0.2mmHg and most preferred at 1 Pa (0.0075 mmHg) and a repeatability errorbelow 10% is most preferred. In the case of position detection (ratherthan transitional/movement detection), accurate pressure readings isrequired. Considering accuracy errors from noise, linearity, andrepeatability, the system must accurately quantify tendon pressures into3 to 5 categories. An accuracy of ±5 mmHg (83.3% of full scale range) ispreferred for detecting basic hand positions, and an accuracy of ±1 mmHg(96.7%) for advanced hand positions, and an accuracy finer than ±0.5mmHg (98.3%) is most preferred. The linearity and repeatabilityaccuracies must exceed the requirements of gross accuracy. Such that 90%accuracy in linearity and repeatability is preferred for basicpositions, 98% for advanced positions, and 99.5% is most preferred.

The signal-to-noise ratio is greater than 100 to 1 (equivalent to 0.3mmHg) is preferred and a ratio of 1000 to 1 is most preferred.

The sensor array preferably has a total vertical height normal to thesurface of the user's skin of 0 mm (conformal contact), preferably nogreater than 0.5 mm and most preferably no greater than 1.1 mm. Thecontrol device has a FPC-type connector preferably with a number ofpositions related to the number of sensors (Sn). In some embodiments,the positions is Sn+1 (for example 9 positions for 8 sensors) andothers, the closest integer greater than or equal to the twice thesquare root of Sn (ceiling(2*sqrt(Sn))) (for example 8 positions for 16sensors). A pin spacing of 1 mm is ideal and can range from 0.25 mm to2.54 mm.

Pressure data using the aforementioned pressure sensors can be acquiredat low power. Power consumption being highly proportional to thesampling rate. 125 Hz & 16 mA being typical of a high performancepressure sensing system. Theoretical maximum for these sensors due tothe response time is 240 Hz. In the case of gesture monitoring, this isexcessive. Human movement is typically less than 1 Hz (changes on theorder of 1 second) and rarely exceed 10 Hz (changes on 100 ms scale).Humans perceive changes near/below 100 ms as near instantaneous andchanges in excess of 50 Hz (20 ms) as instantaneous. A 10 Hz samplingfrequency leads to current of 1.6 mA. Along with inertia sensors (gyro,accelerometers, and magnetometers), total current is typically 2.6 mA.Wearable watches have battery capacities between 100-200 mAh, leading toan operational time of 42-78 hours or 5-9 days of 8 hours of continuedoperation. Power saving features such as sleep mode could extend thisdramatically.

Due to the high SNR of the data, little processing is necessary forgesture acquisition (usually simple arithmetic operations) which consumenegligible amounts of power. EMG signals require wavelet analysis,strong analog amplification, and CPU intensive de-noising which consumeadditional power. For reference, the Myo EMG armband is capable of 1 dayof operation on a single charge and modular EMG units consume 2-4 mA perchannel (or 16-32 mA for 8 channels). Bio-optical systems losesignificant power through radiation (light) emission and dataprocessing. These systems are similar to the heart rate monitors of suchas the Fitbit®, which for reference are capable of 5 days of operationon a single charge. Note that Fitbit® does not do truly continuousoptical monitoring. PPG (optical modules) consume 2.3 mA typically andthe power use scales according to the number of sensors. Using an8-channel optical system +inertia measurement, power consumption wouldbe 19.4 mA, with operational time of 5-10 hours.

In one embodiment, the control device is comprised of a pressure sensorarray that is disposed within a continuously flexible structure withinthe arc of a band or other structure that functions to maintain thesensor array in close conforming engagement with the body appendage. Thepressure sensor array is comprised of material substantially lacking inany of glass, rigid transparent polymers, stainless steel, or lightemitting or detecting apparatus. Although these components may beincluded within the control device, or any component of the datastoring, data processing, logic circuitry, storage, or communicationcomponents of the control device, these structures not included in theindividual pressure sensors of the array.

EXAMPLE 3 Quantitative Analysis of Pressure Sensor Data and Three-PointAnalysis of Body Position

In a preferred embodiment, the pressure sensor data is quantitative. Forexample, a tightly held first (characterized by muscle tension) isquantitatively different than a loosely held first (characterized byfinger flexion and no muscle tension), and is still different from otherhand position such as an open palm. Similarly, varying and discretedegrees of finger flex in can also be resolved as pressure increaseslocal to the tendon controlling finger movement. Data from the pressuresensor array may comprise three separate data points comprised of afirst initial or resting position of the user's appendage where nomotion is occurring, a transitional period during which motion isoccurring away from the first position, such as the user's intentionalmotion of the wrist, hand, or individual fingers, followed by a secondposition quantitatively different than the first position and which isthe result of the motion of the transitional period and results in thesecond position. Additional motions differing from the first position,and/or the second position, and having subsequent transitional periodsmay also be detected and quantified.

Electrical systems (EMG) for gesture detection rely on the detection ofsignals during muscle contraction. This requires electrode proximity tothe contracting muscle driving hand/finger motion and the muscle must beactively contracting. This means only states characterized by activecontraction can be measured. Passive hand positions such a pointedfinger or a loosely held first have no distinct electrical signal. Fordetection of a fist, the hand must be clinched. This limits use to onlydetecting movements/transitions and a prolonged state can only bedetected during contraction which quickly leads to muscular fatigue. EMGsignals are characterized by high levels of noise, originating from EMFinterference, motion artifacts, small (μV) input signals, bioimpedancechanges, and bio-interface changes. The signal amplification andde-noising of these signals in order to arrive at specific gesturedetection is power (typically 2-4 mA per channel) and computationintensive.

Optical systems (as described in 2016/0091980 operate with similarequipment and principles as PPG; photoplethysmogram) rely on a lightsource penetrating and reflecting off body tissues and intensity of thisreflected light being tracked by a detector. The major limitation ofthis system is the power consumption from continuous radiation emission(typically 2 mA per emitter/detector pair) and the susceptibility tonoise. The latter is particularly troublesome. While positional changesin the hand can be detected (that is no active muscular contraction isnecessary), the noise (noted in 2016/0091980 at paragraph [0039]) andshifting baseline of the light signal makes only transitions reliablydetectable. The 2016/0091980 publication at FIG. 9B notes movementdetection and the description at paragraph [0040] specifically notesdetection of movement. The critical distinction in gesture/positiondetection for optical systems that prohibits absolute positionaldetection is that the detected light is not directly related to tendonposition. That is there is no particular luminous flux necessarilyindicates tendon contraction/relaxation. Signals inputted into thedetector are affected ambient light, reflection on the skin, pressurebetween optical system and skin, and tendon/muscle/bone positions.Changes due to noise sources often exceeds changes in tendon position byan order of magnitude or more. In practice, this makes absolute positiondetection (for example a prolong state of pointed index finger) in theabsence of gesture changes difficult if not impossible to determine.

The essential biological parameter being measured by pressure or opticalsystems is tendon displacement due to contraction and relaxation. In thecase of a pressure-based system, this tendon displacement necessarilycreates pressure against a band in tension around the wrist. With aknown band tension, the pressure directly relates to the displacement ofthe tendon. Such that large displacements (such as a first) causepressures of approximately 10 mmHg and small displacements (such aspinky finger extension) cause pressures of approximately 1 mmHg. In awell calibrated system, a quantified pressure in a given location has awell-defined significance to the underlying tissues. In this manner,even in the absence of motion, circumferential pressure maps of thewrist can be used to accurately access the tendon/muscle/bone status anddetermine the hand position/gesture status.

EXAMPLE 4 Learning Mode for Pressure-Based Gesture Analysis

The control device or the companion device are preferably comprised ofstorage means to retain the pressure sensor data that yields a uniquepressure profile comprising a large number of individual aspects ofmotion initiated by the user. The pressure profile signature isquantified for: 1) a value for each of the individual pressure sensors,2) the change in individual values for each of or all of the individualpressure sensors, 3) a plurality of individual or assembled values, anoverall quantitative score generated from one or more metrics resultingfrom input from a plurality of pressure sensors, 4) any of the foregoingat a discrete point in time, 5) any of the foregoing multiple points intime, and including rates of change in the foregoing and changes in therate of change in the foregoing, and all according to the position ormotion by the user.

The control device may also compares the unique pressure profilegenerated by the pressure array to one or more stored values or profilescomprising unique pressure profiles to determine whether or not anindividual user motion or set of motions corresponds to a stored uniquepressure profile, and the comparison can generate any of a signal, a newscore based on the comparison, a determination that the motioncorresponds to a command generated by the control device or the absenceof such determination. In one embodiment, the control device comparesthe unique pressure profile with a stored range of predeterminedpressure profiles and correlates the sensed pressure profile with themost similar stored pressure profile and generates a command that iscommunicated to the companion device. In another embodiment, thecompanion device has a visual or mechanical option displayed on thecompanion device to inquire of the user whether or not the interpretedcontrol or command signal generated by the control device is correct.

The control device may be adapted to filter noise caused by motion bythe user that is not specific to the generation, determination, oranalysis of unique pressure profile or score. The noise can be comprisedof random motion by the user, autonomic physiological functions such asbreathing, heart rate, or any signal that is extraneous or part of abackground signal distinct from the intentional motion of the user. Thefiltering function may be based on pressure ranges, the presence ofknown physiological functions established as part of a baselinemeasurement, or any other factor that distinguishes noise fromintentional user-generated signal resulting from the pressure-sensorgenerated data.

In a preferred embodiment, either of the control device or the companiondevice contains data storage and logic circuitry or functions to permitone or both devices to operate in a learning or teaching mode whereinuser motion is responsive to instructions from either device directingthe user to perform particular motions or gestures that are subsequentlyintentionally performed by the user to provide a stored unique pressureprofile individually for the user and for comparison with later gesturesexecuted in a standard operating mode. The user may also identifyspecific gestures that are associated with unique commands, as directedby the user, so that the user teaches the control device that a specificoutput generated by the control device command is associated with aparticular motion or set of motions or a particular gesture.

In some embodiments, a separate, detachable, and portable control deviceis comprised of at least six pressure sensors embedded in a an arc δhaving an angle of at least 120 degrees of a flexible and wearabledevice that positions the pressure sensors about the circumference ofthe surface of the skin of a user's body part, wherein a firstquantitatively measured pressure value or set of values is associatedwith a first position of an appendage of the user, a quantitativetransitional pressure vale or set of values is associated with movementof two or more physical structures selected from the group consisting ofbones, ligaments, tendons, epidermal layers, muscles, and interstitialtissue, and a second quantitatively measured pressure value or set ofvalues is associated with a second position of the appendage of theuser. The control device is operably connected with a data processorcontaining storage and logic capable of determining a motion by the useris associated with a command to be communicated with the control deviceor with a companion device.

In one embodiment, the plurality of pressure sensors are located in acontrol device comprised of an array of pressure sensors embedded in astrap with at least eight, at least sixteen, at least twenty-four, atleast thirty-two, or at least sixty-four individual sensors disposed tocircumferentially around the strap. The sensor array is operablyconnected to a data processor containing storage and logic capable ofdetermining that motion detected by the circumferential pressure arrayis associated with a command to be communicated with the control deviceor with a companion device. In some embodiments, the companion device isalso worn by the user and operably connected, either by wirelesstransmission or by mechanical connection, to the control device suchthat the companion device is controlled by a portable electronic devicein turn controlled by pressure signatures detected by motion of the userand detected by the control device.

In some embodiments, the control device comprises a pressure sensorarray that is separate and independently located in a structure thatmaintains the companion device at the skin surface proximate to one ormore user's tendons, ligaments bones, or muscles located in an appendageof the user. For example, the companion device can be a smart watch andthe control device may be comprised of a sensor array incorporated intoa band that is comprised of a plurality of sensing regions spaced awayfrom the companion device and that detect a change in pressure at theinterface of the pressure sensor in a region proximate to the smartwatch and across the adjacent surface of the skin of the user.

The invention also includes methods of using the control devicedescribed herein to differentiate from a plurality of individualgestures by the user such that unique gestures can be translated intocommands for controlling the companion device. The method ofimplementing a command based on a user motion may include the steps ofdetermining that a gesture by a user conforms to a predeterminedpressure profile detected by the sensor array. The method may comprise:detecting a signal comprised of a pressure sensor value, wherein thevalue is a quantitative value comparing a unique pressure profile for afirst resting position and a transitional pressure value reflectingmotion by the user, detecting a change in pressure associated withmotion by the user; and determining that the signal corresponds to aspecific command for controlling the control device or the companiondevice.

Referring to the Figures collectively, the invention relates topressure-based motion detection apparatus for detecting a specific bodymotion and translating that body motion into output. The body motionsare converted into a unique pressure signature and translated intocontrol instructions. In some embodiments, the body motion includes aspecific movement of the hand and typically includes a recognizedorientation of the forearm/wrist, palm, and fingers that generate theunique pressure signature. The unique pressure signature resulting fromthe body motion, such as a well-recognized hand gesture, is processed asa measured combination of sensor inputs based on measured pressures,changes in measured pressures, or changes in changes of measuredpressure over time. In this fashion, body motion is quantified based onunique pressure signatures and translated into command and controlinstructions that provide instructions to a control device or to acompanion device operably connected to the control device.

Because the pressure sensors described herein are inexpensive tomanufacture and offer extremely high pressure sensing performance asdescribed in Example 2, a number of sensors can be incorporated into acontrol device offering the ability for a large number of individualpressure monitoring data inputs that separately and simultaneouslydetect discrete motions from a large number of discrete pressuremeasurements resulting from the position of motion of physiologicalstructures under the skin. The large number of quantitative data inputspermit extremely sensitive and selective unique pressure profiles to beassembled that are discrete and distinctive of specific motions of thebody. The pressure sensor array can, therefore, detect body specificmotions including retraction, extension, expansion, contraction,rotation and virtually any other motion by the user and can be eithervoluntary or involuntary and spontaneous and intentional such as motionof the hand in a preselected gesture, or passive and autonomic, such asbreathing, pulse, or blood pressure.

Specifically with respect to motions of the hand and wrist that aredetected by pressure changes resulting from unique configurations of theforearm/wrist, hand, and fingers, tendon measurements, individualcomponents or collected movements are determined and may becharacterized as flexion, extension, abduction, and adduction andcombinations of each measure as a score with a weighting profile toevery motion, position, change in motion or position over time or changein the rate of change over time. Flexion is generally defined as amotion of the hand wherein the palm moves toward the body side,extension is generally described as a motion of the hand wherein thepalm moves away from the body side. Abduction is generally defined as amovement of the hand wherein the palm moves toward the little fingerside and adduction is generally defined as a movement of the handwherein the palm moves toward the thumb side. Finger flexion is definedas the motion of the finger toward the wrist and extension is defined asthe straightening of the finger.

With respect to any point on the body, the movement can be characterizedas an absolute or relative motion along any of the X, Y, or Z axes, anyrotation around an axis θ, γ or ϕ, changes in the position of any pointor set of points over time, as well as changes in the rate of change ofmotion or rotation over time. In addition to the pressure-based sensorarray, additional components such as accelerometers, gyroscopes, andmagnetometers can be incorporated into the control device with similarmeasurements of change, rate of change and change in rate of change overtime. In a preferred embodiment, three accelerometers, three gyroscopes,and three magnetometers are incorporated with at least eight ion-basedpressure sensors used to generate the unique pressure profile. Thecombination of absolute or relative motion can be incorporated withchanges in absolute or relative pressures to create a high selectivityand high specificity motion and pressure-based command that istranslated into a specific output, such as a command or control functionfor a companion device.

Most motion at the elbow and shoulder, and in some cases the hand, haveno distinct pressure affects at the wrist and motion by the user, suchas displacement along the X, Y, or Z axes, and comprised of some degreeof linear or arcuate motion or rotation, our capable of being analyzedas independent metrics. Some user motions, such as internal and externalrotation of the hand, palm point up or down, because of both pressureand rotational changes that are detectable at the surface of the skinusing the pressure array. Combinations of gestures that combine bothmovement and rotation of the appendage generate a much greater selectionof distinct position states and characteristic movements that may beanalyzed and scored. For example, a thumb up position, a thumb sideposition, and a thumb down position are all distinct position states androtations wherein a combination of pressure sensors and motion sensorsas described herein can yield both pressure signals and motion signals.Repeat gestures, such as tapping the index and thumb together twice, canprovide a greater degree of accuracy for interpretation of any motion orgesture and adds to the signal component of a pressure score that isdistinct from other common motions properly characterized as noise.

In operation, the end result is that pressure changes sensed around aregion of the body of the user are translated into commands for acompanion device such as a graphic or video display controller, a gamingconsole controller or a computer user interface. As perceived by theuser, body motions are instantaneously translated into discerniblecommands any companion device. Accordingly, when the user executes ahand gesture, the composition of the underlying tissue exerts a uniqueand characteristic pressure profile on the sensor array and thepressure-sensor array, potentially in combination with other motionsensing components, translates the gesture into a specific command thatis instantaneously executed in the companion device.

The control device or the companion device is comprised of logiccircuitry for comparing any value, set of values or score a storedreference or comparison value, optional treated as a threshold, todetermine that the body motion corresponds to a stored body motionparameter that is paired with a specific control command. If the bodymotion is determined to match the stored value, profile or score, thecontrol device generates the pre-determined command. For example, any ofa forearm/wrist, hand, or finger gesture can be to be dependent ongeneration of a specific pressure detection signature as a collection ofmovements of each of the forearm, wrist, hand, or fingers or anydiscrete physiological structure can be separated such that the movementof the hand in any subset of fingers is distinguishable from a differentsubset of fingers together with a similar or dissimilar hand gesture. Inthis fashion, any of the individual physiological components, theposition, or motion thereof can be assigned as a null set or controlvalue with the individual movement of any physiological structuredictating the output from the control device of a specific control orcommand.

Equivalent distinctions in quantitative measures can also be based onabsolute or relative time signature such that the absolute or relativevalue of any pressure reading can be expressed or analyzed as a functionof time together with or separate from any other measurements. In thisfashion, a time interval T1 can be determined for any particularpressure sensor reading, profile or score such that the difference inthe time interval from time point T12 time point T2 solely determines adifference in the output from the control device. In other words, aslower motion is distinguishable from a faster motion and the differencebetween the time necessary to undertake any motion or change in theposition can, in of itself, drive degeneration of a command control.

As noted above, the logic circuitry of the control device can be adaptedto filter a noise signal generated by extraneous pressures such as thosegenerated by pulse, including a heart rate that changes over time,breathing, blood flow or other autonomic functions. For this purpose,the control device may accept input from reference sensors that arespecifically located to account for noise separate from the primarysensor array signal. The control device further may also comprise forsending pressure sensor array output to logic circuitry located in thecompanion device or elsewhere such that the pressure sensor array datacan be further processed to generate command-and-control signals asdescribed herein. In such an embodiment, the companion device comprisesa corresponding receiving unit such that the control device in thecompanion device wirelessly communicate with each other.

In the method of the present invention, the pressure sensor arrayinitially measures a starting, resting, or original first position basedon quantitative pressure sensor data and prior to the measurement of anysignal from any of the accelerometers, gyroscopes, or magnetometers.Subsequently, the change in pressure sensor array values caused bymotion of the user's body is determined and quantified relative to thefirst position, and optionally in combination with input from any of theaccelerometers, gyroscopes or magnetometers. Subsequently, following thetransitional movement phase, the pressure sensor data or changes in thepressure sensor data are determined for a distinct second position thatis distinct from the first position. The difference between any of thefirst position, the transitional phase, or the second position ismeasured and correlated to position or motion of the user's body. Forexample, where the body motion is a hand motion comprising movement ofthe entire hand or a movement of a part of the hand, such as themovement of one or more fingers relative to another part of the hand,the difference in position of the hand is determined based on thedifference in pressure sensor values or comparative scores is determinedto be indicative of a predetermined hand movement and is sent by thecontrol device 1 to the companion device to be controlled by handmovements.

The method may include a termination or verification step wherein adisplay apparatus or sensory input is provided to the user to affirm ordeny that the correct command or control indicator has been generated bythe gesture performed by the user. Upon selection by the user, thegesture is disregarded and the data comprised of measurement from thefirst position, through the transitional phase, to the second positionis discarded by the logic circuitry. If the gesture is confirmed, thenthe command or control is executed.

Typically, signals from accelerometers, gyroscopes, and magnetometersare independent of the signals generated from the pressure array but canbe analyzed together with pressure array data to generate output fromthe control device. In some cases, pressure and position sensors can belinked and scored together. For example, a user motion primarily of theelbow and shoulder results in fewer signals in the pressure sensors anda greater signal in the motion sensors, whereas motions of the handresult in a greater signal from the pressure sensors and less from themotion sensors. One significant exception is the internal/externalrotation of the hand (palm up or palm down) wherein caused by rotationof the elbow wherein pressure changes at a pressure array disposed onthe wrist may generate the predominant signal greater than themotion-based signal.

Although in above described embodiments the detected body motion is usedto control a companion device, in some embodiments, the body motion canbe used to control the control device itself such as to power the uniton or off or to initiate communication with a companion device.

Referring specifically to FIG. 1, six individual metrics (G0-G5)represent individual elements of a quantitative pressure detection dataprofile of the control device of the invention. The combination ofmetrics, based on the individual amplitudes of the individual metricsG0-G5 yields a unique and quantitative gesture detection score based onthe specific, individual pressure values input from the sensor array andmay be reflected as an area based on any combination of the magnitude ofcontribution of the individual metrics G0-G5. In FIG. 1, the combinationof the individual metrics is shown by the shaded area disposed aroundthe center point of the graphic. Those of skill in the art willappreciate that this graphic and the specific representation of theindividual metrics G0-G5 is only chosen for convenience and any similargraphic could convey the same concept of a combined score based onseveral measurements of human individual metrics. Furthermore, thespecific number of individual metrics as illustrated in FIG. 1 is onlyrepresentative. Independent of the total number of sensors, a differentnumber of individual metrics could be chosen. Therefore, the number ofindividual metrics could be less than, equal to, or greater than thetotal number of sensors.

In any configuration, the input from the individual matrices may be usedto generate a quantitative score based on the individual or collectivecontribution of the matrices. Furthermore, the contribution of theindividual matrices may be weighted such that one or more metricscontributes more or less to the final score. Still further, eachindividual metric may be analyzed over time to determine changes in themetrics over time including the rate of change of any individual metric,or a collection of matrix, over time. The example of FIG. 1 shows sixindividual metrics G0-G5 from pressure sensor data. Additionally,separate sensors of non-pressure data could be integrated into theprofile to either alter the shape of the profile in the X-Y plane orcould provide an additional component, such as a Z direction out of theplane of the page, to further enhance the profile. As noted above, theprofile can be static or dynamic in the changes in any of the matrices,including their absolute or relative value, change in value, rate ofchange in value, rate of rate of change, and correlated with the gestureor combination of gestures.

Any absolute or relative measurement of the motions, ranges, or patternsof motions, can be analyzed and used to generate a quantitative scorethat reflects the combined pressure measurements both individually andin comparison to a prior individual motion or assembled set of motions.Individual or collective motion scores can be correlated with types ofuser-performed motions that are characteristic of a function intended tobe performed by the user or a control or command intended by the user tocontrol a companion device.

Typically, the individual metrics will not be matched one-to-one to aspecific number of sensors or a particular anatomical structure such asa tendon, and because each metric may be a contribution from one or morepressure sensors, the combination of the metrics reflects an combinedpressure profile that has a combined contribution from multipleanatomical structures. The pressure profile score corresponding tospecific individual or discrete motions, range of motions, or assembledsets or subsets of motions can be recognized and used to establish amotion pattern or deviation from a pre-existing pattern.

Referring specifically to FIG. 2, a cross-section of a human wrist showsthe position and orientation of individual physiological structuresincluding fourteen tendons T1-T14, the radius and ulna bones, and otherinternal anatomic structures such as cartilage, interstitial tissue,nerves and joints. The placement of a plurality of individual pressuresensors in close conforming engagement with the outer dermal layers ofthe wrist generates unique and quantitative pressure profiles based ondifferent configurations and motions of the forearm, wrist, hand, andfingers. Because of the large number of anatomical structures and theirunique position and orientation throughout the range of motion of ahuman user, the changes in pressure at the surface of the skin can varytremendously allowing their accurate measurement with the placement ofenough pressure sensors having adequate selectivity and sensitivity todetect these changes.

As noted above, a pressure sensor array of the invention may beincorporated into a band structure that surrounds an appendage, such asthe wrist, to play sensors at locations that are capable of detectingmotion of the underlying physiological structure as reflected as changesin pressure at the surface of the skin. As is apparent from FIG. 2, andas described in greater detail below, the tendons, bones, and otherphysiological structures are not uniform in their distribution in eitherthe horizontal or vertical direction. Similarly, the positioning andshape of the individual structures changes as one moves up or down thearm and so the position of a band around the wrist may be highlyindividual to the user. The selection and positioning of the pressuresensors in the array can be tailored to the specific location of each ofthe tendons, bones, or other structures to specifically detectdifferences in position with certain motions.

As is apparent from the relative positioning of the sensors, thepressure reading from an individual sensor will reflect thosephysiological structures that are proximate to the point of contactbetween the sensor and the region of skin in confirming engagement withthe sensor. Because the physiological structures in the wrist are notoriented symmetrically relative to the external surface of the skin,individual sensors will necessarily reflect pressure changes from adifferent combination of tendons, bones, muscles, and any otherstructure yielding a differential pressure to the sensor. Accordingly,the pressure data imparted to an individual sensor may be unique to itslocation around the circumferential exterior of the wrist. For thisreason, the band in which the sensors are disposed is designed so thatit is placed in the same orientation around the wrist on each individualuse. For example, the band may have a tensioning element that keeps theend in conforming engagement with the outer surface of the skin, andserves to orient the positioning of the sensor array so that individualsensors are repeatedly sensing the same combination of physiologicalstructures so that the sensor array data profile is producing similardata on repeated use and so that the data sensor profile can be storedin a data storage element for comparison between individual uses by theuser.

Referring specifically to FIGS. 3A and 3B, the control device 10 iscomprised of a plurality of sensors, numbered #1-#8 in FIG. 3A and#1-#16 in FIG. 3B, and a case or housing 11 for containing data storage,power, and logic circuitry to detect and analyze the unique pressuresignatures as described herein. Referring to FIG. 3A, the sensor array20 is comprised of the collection of the individual sensors #1-#8 heldin close conforming engagement with the outer surface of the user'sappendage. As described above, the sensor array is preferably disposedin a band that has a tensioning element for retaining contact betweenthe sensor array and the outer surface of the skin to maximize detectionof changing pressures at each point about the array. As with a watchband, the design of the band and tensioning element places the sensorarray repeatedly in the same position relative to the underlyingphysiological structures of the user so that each subsequent use canreliably compare the pressure sensor data profile from a prior use orcalibration to interpret the gestures of the user must accurately.

In the embodiment of FIG. 3A, the sensors around the entirecircumference of the appendage with the exception of the portionoccupied by the case 11, and so surround approximately 320° of theappendage assuming approximately equal size between the case and anyindividual sensor. The embodiment of FIG. 3 A represents a recognizableexample of the sensor array 20 disposed in a watch band with thefunctional portions of the watch element disposed in the case 11 whichcan be attached to, or incorporated into the band as with a traditionalor digital watch. Preferably, the sensors surround at least 180°, 200°,220°, 240°, 260°, 280°, 300°, 320°, 340°, and 360°. The number ofsensors may be greater than, equal to, or less than the number oftendons. Assuming the presence of 14 tendons as in FIG. 2, each of theeight sensors in the embodiment of FIG. 3A, each sensor is receivingpressure data from more than one tendon as well as the underlying bone,ligaments, joints, subdural tissue, and vasculature. Furthermore,although the individual sensors in the array 20 in both FIGS. 3A and 3Bare substantially equal in size and are equally spaced around theappendage, other embodiments may include sensors having different sizesand where the spacing is eccentric around the appendage to takeadvantage of unique pressure sensors that may arise from the underlyingphysiological structures at different points around the circumference ofthe wrist.

Referring specifically to the embodiment of FIG. 3B, the sensor array 20is comprised of sixteen individual sensors #1-#16 that surround theentire appendage of the user such that the case 11 is separate from thedermal layer and is disposed along the surface of one or more of themembers of the sensor array 20. Accordingly, the coverage of the sensorarray around the circumference of the appendage is 360°. As describedabove, in this embodiment, the number of sensors #1-#16 outnumbers the14 individual tendons and the selectivity and specificity of the controldevice 10 is increased because more than one sensors can be designatedas interpreting sensor data input from an individual tendon. Thisconfiguration increases the sensitivity and specificity of the arrayand, in terms of interpreting individual pressure-based profiles,increases the accuracy of the array. Moreover, as the number ofindividual T₁-T_(n) sensors in the sensor array 20 increases, smallerchanges in motion by the user may be detected and analyzed to generatemore precise pressure signature profiles and more subtle motions andgestures may be detected.

Referring specifically to FIG. 4, the normal motion of a human appendagemay be detected simply by simple pressure changes as reflected in theoutput from the sensor array and correlated to a number of motions orgestures based on distinct and identified changes in the input from thearray. Specifically, with respect to motions of the arm, hand and wrist,detected pressure changes resulting from such individual and collectivemotion of the arm, hand, and wrist can be detected and correlated toindividual motion components. The individual components of the motionmay individually or collectively be characterized as flexion, extension,abduction, and adduction and combinations of each measured, andoptionally as a score with a weighting profile to every motion,position, change in motion or position over time or change in the rateof change over time. Each distinct combination of motions from the arm,hand, and wrist, generates an identifiable pressure data profilecharacteristic of the particular motion or gesture that can be used togenerate an output signal to the companion device, or stored for furtheranalysis, comparison with the future set of motions or gestures, or usedas part of a calibration procedure.

Referring again to FIG. 4, flexion is generally defined as a motion ofthe hand wherein the palm moves toward the body side, extension isgenerally described as a motion of the hand wherein the palm moves awayfrom the body side. Abduction is generally defined as a movement of thehand wherein the palm moves toward the little finger side and adductionis generally defined as a movement of the hand wherein the palm movestoward the thumb side. Finger flexion is defined as the motion of thefinger toward the wrist and extension is defined as the straightening ofthe finger. “N” indicates that the orientation of the anatomicalstructure is in a neutral status or position. Level 1 pressure profilesare easiest to detect and are comprised of arm movements, flexion orextension of the palm, and opening or closing of the hand as detected byfinger motion. Level 2 changes in motion are more difficult to detectand are comprised of adduction or abduction of the palm. Level 3pressure signatures are more difficult to detect and requiredifferentiating between individual motions of the fingers.

As indicated, measuring differences between the thumb and index finger,together or separately with other fingers or anatomical structuresallows the pressure data profile to distinguish between forming an“okay” signal, pointing the index finger, giving the “good” or “thumbsup” sign, extending forefingers, or forming a “gun grip” with thefingers and palm, and the opening or closing of the palm.” As notedabove, the pressure data profile resulting from each set of motions canbe translated into an output signal, stored or used as part of ananalysis or calibration procedure wherein a pressure data profileresulting from a range of motions is stored and used for comparison to afuture action that results in an output signal and a definiteconstruction to a companion device. For example, a user who desires togive the “thumbs up” sign to activate a computer terminal may beinstructed to repeatedly perform that structure so that a characteristicset of motions is measured by the pressure sensor array to generate apressure data profile specific for that user and specific for themeasured pressure differences resulting from the selected motion of thephysiological structures of the user's wrist. Once an adequate baselineof data is collected, the device is functionally calibrated so thatfuture characteristic motions or gestures by the user are recognized andtranslated into an output signal.

Referring to FIG. 5, a simple listing of commands shows how theindividual motion of the wrist, hand, and fingers could be used toassign individual functions to a companion devices such as a gamingcontroller, a computer mouse, or within a software program such asMicrosoft® PowerPoint® to generate individual commands. Taking theexample of the computer mouse in the central column of FIG. 5, openingthe hand gives the instruction to “drag and release” the fieldhighlighted by the mass controller. Closing the hand commands draggingthe field while flexion of the hand indicates “undo” or “back” whileextension of the hand indicates “forward.” Forming a circle using thethumb and index finger results in a output signal, command, or controlfor a “left click” while forming a ring with the thumb and ring fingeris a “right click.” Abduction or adduction generate the control commandfor rolling up a page or rolling down a page respectively.

Referring to FIG. 6, FIG. 6 is a chart showing representative change inphysiological interfacial pressure across fourteen individual tendonslocated in the right hand wrist and designated T1-T14 as in FIG. 2 andFIG. 3A-3B. Although the numbering and orientation is arbitrary, in thepressure signature, motion detection, and gesture command scheduledescribed in FIG. 6, and in the exemplary device of FIG. 3B, pressuresensors measure and quantitate, using the five pressure changecategories indicated by the arrows, changes across tendons #1-6 from theflexors on the palm side of the wrist/forearm and tendon extensors onthe backside of the wrist/forearm. The wide range of detected pressurechanges for each of the fourteen tendons for a particular user motionare measured by these criteria and translated into gestures. Referringto the individual boxes of FIG. 6, blank fields indicate no change inpressure, single downward arrows indicate a small reduction in pressurevalues, dual downward arrows indicate a larger reduction in pressurevalues, single upward arrows indicate a small increase in pressurevalues, and dual upward arrows indicate a larger increase in pressurevalues. By correlating the specific changes to pressure at each of thetendons, a pressure data profile comprised of a plurality of pressurechange data is detected and analyzed for pattern recognition andcorrelation to distinct gestures. The left axis contains examples of atleast 11 individual orientations or command-and-control functions thatcan be assigned to the specific combination of pressure changes acrossthe tendons as measured.

Accordingly, for the gesture of opening the hand, the pressure sensorarray 20 as shown in FIG. 3B, a large pressure increase is detected fortendon #1, small increases in pressure are detected for tendons #2-#4,large pressure increases are detected for tendons #5-#10, small pressuredecreases are detected for tendons #11-#13, and a large pressureincrease is detected for tendon #14. Similar changes in pressure can becorrelated across the fourteen tendons for the remaining gestures shownin the left-hand column. Although the numbering and orientation isarbitrary, in the pressure signature, motion detection, and gesturecommand schedule inflected in FIG. 6, and in the exemplary device ofFIG. 3B, pressure sensors generate the specific pressure data profilethat is further processed and may be converted to an output signal to acompanion device. As noted above, because the individual physiology andselected motion of a user are unique to that individual, unique pressuresensor data can be used to generate the pressure data profile that isunique to the motions or gestures of an individual. Accordingly, inpractice, the same person making the same “okay” sign will yield anidentifiably different pressure data profile from a different person.These differences can be used to identify an individual for securitypurposes and activate unique identifier such as sign-ins, passwords,locks, and any other mechanism where individual identification isdesired. Importantly, in contrast to traditional input devices such as akeyboard or mouse, the gesture is detected solely from the sensor arrayaffixed to the appendage of the user and so no physical contact isnecessary between the user and the input device. When integrated into awatch, individual gesture may also operate any function of the watchincluding instructions to send or receive messages, place or receivetelephone calls, actuate electronic devices and user interfaces, and bymaking simple gestures, generate output signals to control a widevariety of electronic devices based on individualized pressure dataprofiles that are unique to a user.

Although the disclosed examples have been fully described with referenceto the accompanying drawings, it is to be noted that various changes andmodifications will become apparent to those skilled in the art. Suchchanges and modifications are to be understood as being included withinthe scope of the disclosed examples as defined by the appended claims.

The claims are:
 1. A device for detecting motion by a user comprising: apressure sensor array comprising a plurality of individual flexibleionic pressure sensors spaced around and integrated into a support bandhaving a tension element for keeping the sensors in contact with skinaround an appendage of the user, wherein the plurality of sensors arespaced around the band to detect pressure changes resulting from motionof the user and wherein each of the plurality of sensors conforms to anexternal curved surface of the body of the user; and a pressure dataprofile resulting from motion of the user detected by the ionic flexiblepressure sensor array, wherein the pressure data profile comprises aplurality of differential skin pressure measurements detected frommotion of at least 6 different physiologic structures proximate theplurality of sensors.
 2. The device of claim 1, wherein the pressuresensor array is comprised of at least six individual flexible ionicpressure sensors disposed on the inner surface of a band sized tocircumferentially surround a human wrist.
 3. The device of claim 1,further comprising a data storage unit containing the pressure dataprofile from the user and comprising an output command based on changesin pressure data profile correlated with a gesture by the user.
 4. Thedevice of claim 1, wherein at least ten individual flexible ionicpressure sensors are spaced around the band.
 5. The device of claim 3,wherein the pressure data profile comprises ionic pressure sensor arraydata correlated to motion of the arm and fingers of the user.
 6. Thedevice of claim 1, wherein the pressure data profile is comprised ofpressure measurements having a sensitivity of less than 1 mmHg.
 7. Thedevice of claim 1, further comprising a separate sensor selected fromthe group consisting of an optical sensor, a gyroscope, a magnetometer,and an accelerometer, and combinations thereof, wherein the pressuredata profile is further comprised of data from the separate sensor andcombinations thereof.
 8. The device of claim 1, wherein the individualflexible ionic pressure sensors of the array each have a height lessthan 1.5 mm.
 9. The device of claim 1, further comprising a companiondevice selected from the group consisting of a digital watch, a digitaltelephone, a computer, a video game controller, a digital lock mechanismand combinations thereof.
 10. A method to translate an identifiedgesture of a user into a control signal for a companion devicecomprising: generating a pressure data profile input resulting from theidentified gesture of the user that is detected by a pressure sensorarray comprising a plurality of individual flexible ionic pressuresensors conforming to an external curved surface of a body and detectingdifferential skin pressure measurements from at least six differentphysiologic structures of the user, correlating the pressure dataprofile input from the identified gesture into an output signal;transmitting the output signal to the companion device to cause thecompanion device to perform a function correlated with the identifiedgesture of the user.
 11. The method of claim 10, wherein the step ofgenerating the pressure data profile is comprised of measuring of atleast six individual pressure sensor values from the flexible ionicpressure sensors circumferentially disposed around, and in contact with,the skin of a human wrist.
 12. The method of claim 10, wherein thecorrelating step is comprised of comparing the pressure data profileinput with a stored pressure data profile unique to the user andcomparing the stored pressure data profile to the identified gesture ofthe user.
 13. The method of claim 10, wherein the step of comparing theinput pressure data profile and the stored pressure data profile iscomprised of comparing pressure changes attributed to motion of thefingers and tendons of the user at a first time with pressure changesattributed to motion of the fingers and tendons of the user at a secondtime.
 14. The method of claim 10, wherein the input pressure dataprofile is comprised of a pressure measurement from the skin of the userproximate to the at least 6 individual tendons from at least 10 flexibleionic pressure sensors integrated into a band held in conformingengagement with the wrist of the user.
 15. The method of claim 10,wherein the input pressure data profile has a sensitivity of less than 1mmHg.
 16. The method of claim 10, wherein the input pressure dataprofile is further comprised of input from a separate sensor selectedfrom the group consisting of an optical sensor, a gyroscope, amagnetometer, and an accelerometer, and combinations thereof.
 17. Themethod of claim 10, wherein the step of generating an output signal tocontrol the companion device is comprised of a data component thatidentifies the individual user as against other users such that thecompanion device will not operate without the data component of theindividual user.